Rack drive



W. LOHS RACK DRIVE May 19, 1942. v

Filed May 1s, 1940 6' lll/@Olli 6 IlllllllllllllIIIIIIIIIIII So! 1 (S) ff@ @NW1 Sws ATTORNEY.

Patented May 19, 1942 2,283,746

UNITED sTATEs PATENT lOFFICE RACK DRIVE Willy Lohs,` Berlin-Siemensstadt, Germany, asl signor to Siemens Apparate und Maschinen Gesellschaft mit beschrnkter Haftung, Berlin,

Germany, a corporation of Germany Application May 16, 1940, Serial No. 335,639

In Germany May 4, 1939 l claims. (Cl. 74-422) v The present invention relates to improvements .from thel wheel v2 to a corresponding` second in racks and driving means therefor. More parwheel 2rof the same stage for reversing the diticularly, the invention relates to a rack especially rection of rotation. The next stage is then for operating adjusting rods in airplanes, land driven vby the pinions 3 and 3f mounted on comto multi-stage reduction gearing of a very high 5 mon shafts with the wheels 2 and 2', respectively. speed reducing value for driving said rack. The pinions 3 and 3 each drive twofwheels 4 and It is an object of the invention to obtain a rack 4Q, respectively, which are connected through drive of the above mentioned character which pinions 5 and 5'- and wheels Ii` and 6 with the requires considerably less material and space l pinions 4'I-and 1', respectively. The rotary force and is of lighter weighty than similar devices l0 is then transmitted by each of the pinions 1 and known heretofore, so as to be especially usefulpin 1 to two followingv gear wheels 8 and 8 each airplanes, for instance, for operating the-advhaving mounted on its shaft a driving-pinion justing rods of the landing gear and the like. 9 or 9', respectively all of which are in engage- Another object of the invention is to provide a ment with the gear teeth of the rack Il)` having rack drive of high eciency and low cost of gear teeth on both sides thereof. The rack I0 manufacture which only requires small spur gear is therefore driven by four wheels-9 engaging wheels, one side thereof and four other wheels 9 engag- For attaining these objects, the transmission of ing the other side. i the driving force from the driving pinion to the In the embodiment ofthe invention shown in driven.rack which is preferably provided with Figs. 4 to 6, the rotary force of the motor shaft teeth on both sides, is eiected according to the is transmitted to the rack I0 by a gear consisting invention by several stages or branches of gears of six stages. In the rst stage, the shaft of the so as to drive the rack by means of one or more motor lM (Fig. '7) carries 'a Worm Wheel S which rows of gear wheels, preferably by two parallel is in engagement with the wormwheels R and rows mounted on opposite sides of the rack. A 25. R' the shafts of which each carry a driving pinfurther advantage hereby obtained consists in ion f or l', respectively, which are in engagement "that the entire gear requires no ymore space in with the gear wheels 2 and 2', respectively. The any direction than that required by a hydraulic .neXt Stage 4is driven by. the DnOIlS v3 and 3' adjustingr drive which may be used in exchange mounted on `common shaftsl with the wheels 2 thereof and which may comprise a piston and 2', respectively. TheL force is then transmounted directly on the adjusting rod and'mov-A mitted from the pinions 3 and 3' through the able longitudinally in a compression cylinder. gear wheels 4 and 4 and the pinions 5 and 5 to Further objects, features and advantages of the gear wheels 6 and 6', respectively. These v the present invention will appear from the fol- Wheels are, on one side, in driving engagement lowing detailed description and the accompany- With the Corresponding Wheels fillV and 5a', Ie-

ing drawing, in which i spectively, while on the other side, Athe rotary Fig. 1 is a diagrammatic front view of one emforce is transmitted through the shafts of the bodimoni; of the invention, wheels 6 and 6 to thelpinions 'l and 1', respec- Fig. 2 is a side view thereof, tively each of which,.in turn, drives two following Fig. 3 is a plan view of the embodiment shown 40 Agear Wheels 8 01 3'.\1eSDeCtVe1Y- EaChOf these in Figs. 1 and 2. e AWheelscarries on its shaft a driving pinion 9 or Fig. 4 is a diagrammatic front view of anotherI 9', respectively, Which engage the rack` I0. In a embodiment of the invention, corresponding manner, eachA of the -gear wheels Fig, 5 is a, Sido view thereof, 6a and 6a carries on its shaft a pinion 1a or 1a', Fig. 6'is a plan view of the embodiment shown 45 respectively, each of which is in drivingengagein Figs, 4 and 5, and ment with two gear wheels 8a and 8a'- Each of Fig. 7 is a diagrammatic view showing the these wheels` has mounted on its shaft a driving manner of connecting the gear according to Figs. pinion 9a or 9a'., respeetivelyfengeging the rack 4 to 6 to a driving motor. l0. The four pinions 9 and 9' are thus in driving The gear according to Figs, 1 bo 3 consists of 50 engagement with one side of the rack I0 and the five stages and is made up as follows: The drivfour other pinions 9a and 9a' with the other side ing force of the shaft W which may be driven, thereof. for example, by an electromotor (not shown), is The embodiment according to the` invention as rst transmitted from the driving gear wheel I Shown in Figs. 4 t0 6 e180 has the advantage that to the Wheel 2 of the next following stage and 55 the shaft of the motor M with the worm wheel S thereon may be shiftable to some extent x-ina-xial direction relative to the worm wheels 1R and R' which may be mounted in a separate-gear casing together with the gear wheels `I to 9. The fact that the axis of the motor may be parallel -With 1. A rack drive comprising a single `driving means, a rack having toothed portions on opposite sides thereof, a reduction mechanism comprising a plurality of rotatable gear means dening a plurality of gear stages, pinions mounted for rotation with each of said gearmeans-so that the pinions of the gear means of the iirst gear stage engage with a gearzmeans of the next gear stage and the pinions carried by the gear `means of the last-named gear stage engage with a gear means of the succeedinggear stage ina manner whereby the gear means of the lastgear stage are driven by the pinions ofthe preceding gear stage, the gear means of the rst gear 4stage being driven by said driving means, and the pinions of the gears means of the last gear stage engaging said rack at the opposite toothed `portions thereof for moving said rack transverselyof said reduction mechanism.

2. A rack drive comprising a `single ydriving means, a rack having toothed portions on opposite sides thereof, a reduction mechanism comprising a plurality of rotatable gear vmeans deflning a plurality of gearstages arranged above said rack, said gear means being .arranged ,into two parallel `gear trains, one of the gear trains being, above one toothed :portion of the rackand the other gear train-being above theother toothed portion of the rack, pinions mounted for `rotation with each of the'gear means, `each of YsaidA pinions meshing with the gear means of thenext succeeding gear stage, said `reduction mechanism having a power input end at which one of said gear means engages with and is driven by said driving means, a second of said gear means drivably engaged by said one gear means, the `pinion of said one gear means meshing with a gear means of one of said gear trains and the pinion of the second of said gearmeans engaging `with a gear means of `the second gear train, said reduction mechanism further having an output end at which the gear means `of the last gear stage are driven by the pinions of the Vgear means of the preceding gear stage of each of said gear trains, and the pinions of the last-named gear means drivably engaging the opposite toothed portions of said rack for moving the latter transversely of said reduction mechanism.

3. A rack drive comprising a single `driving means, a rack having toothed portions on opposite sides thereof, `a reductionrmechanism comprising a plurality of Arotatable gears dening a `plurality of gear stages arranged above said rack, I,said gears being arranged into two parallel gear trains, one of the gear trains being above one `toothed portion of the rack and theother gear train `being ,above the other toothed portion of .the rackpinions mounted for rotation with each .of the gears, each of said pinions meshing with Athe gear of the next succeeding gear stage, said reduction mechanism having a. power input end :at lwhich one of said gears engages with and is driven by said driving means, a second of said gears drivably `engaged by said one gear, the Apinion of said `one gear meshing with a third of said gears contained in the rst gear train and 'the `pinionrof the second of said gears meshing prising a plurality of rotatable gears dening a plurality of gear stages, `pinions mounted for rotation with each-of said gears, each of said pinions meshing with the gears of the next succeeding gear stage, said reduction mechanism having a power input end at which one of said gears engages with .and is driven by said driving means, said reduction mechanism further having an output end at which other of said gears are driven by the pinions ofthe gears of the preceding gear stage, `and `the pinions of said other gears drivably engaging the Vopposite toothed portions of said rack for moving the latter transversely of said Areduction mechanism.

`5.1i rack drive comprising a single driving means, a rack having toothed portions on opposite sides thereof, a reduction mechanism comprising a plurality of rotatable gears dening a plurality of gear stages arranged above said rack and a plurality of rotatable gears dening a plurality of gear stages arranged below said rack, pinions mounted for rotation with each of said gears, each oi said pinions meshing with the gear of the next succeeding gear stage, said reduction mechanism having a power input end'at which one of said gears above said rack and one of the gears below said rack are driven by said driving means, va power output end for said reduction vmechanism comprising other of said gears above said rack driven by the pinions of the gears of the `preceding gear stage and other of said gears below said rack driven by the pinions of the gears of the Vpreceding gear stage, and the pinions of said other .gears `above and below said rack drivably engaging the opposite toothed portions of said rack for moving the latter transversely of said .reduction mechanism.

WILLY LOHS. 

